Department of Tumor Biology, 3rd Faculty of Medicine, Charles University Prague, Czech Republic.
Crit Rev Oncol Hematol. 2013 Nov;88(2):338-56. doi: 10.1016/j.critrevonc.2013.05.002. Epub 2013 Jul 5.
The major cause of death due to cancer is its metastatic deposit in numerous tissues and organs. The metastatic process requires the migration of malignant cells from primary sites to distant environments. Even for tumors initially spreading through lymphatic vessels, hematogenous transport is the most common metastatic pathway. The detachment of cancer cells from a primary tumor into the blood stream is called epithelial-mesenchymal transition (EMT). As these cells circulate further in the bloodstream they are known as circulating tumor cells (CTCs). The CTC population is highly resilient, enabling the cells to colonize a foreign microenvironment. Alternatively, cancer stem cells (CSCs) may arise from differentiated cancer cells through EMT and an embryonic transdifferentiation process. The presence of CTCs/CSCs in blood seems to be a determining factor of metastasis. This paper reviews various methods of clinical cancer detection as well as the biology and molecular characterization of CTCs/CSCs. Our goal was to summarize clinical studies which used CTC/CSCs for prognosis in patients with breast, colorectal, prostate, lung, ovarian, and bladder cancer.
癌症死亡的主要原因是其在众多组织和器官中的转移性沉积。转移过程需要恶性细胞从原发部位迁移到远处环境。即使对于最初通过淋巴管扩散的肿瘤，血源性转移也是最常见的转移途径。癌细胞从原发性肿瘤脱离并进入血流的过程称为上皮-间充质转化（EMT）。当这些细胞在血液中进一步循环时，它们被称为循环肿瘤细胞（CTC）。CTC 群体具有高度的弹性，使细胞能够在异质微环境中定植。或者，癌症干细胞（CSC）可能通过 EMT 和胚胎转分化过程从分化的癌细胞中产生。血液中 CTC/CSC 的存在似乎是转移的决定性因素。本文综述了临床癌症检测的各种方法以及 CTC/CSC 的生物学和分子特征。我们的目标是总结使用 CTC/CSC 进行预后的临床研究，这些研究涉及乳腺癌、结直肠癌、前列腺癌、肺癌、卵巢癌和膀胱癌患者。
